1. Technical Field
This disclosure relates to voltage sensing circuits, including voltage sensing circuits that measure differential voltages across high impedance nodes with high common mode voltages.
2. Description of Related Art
Sensing the voltage across two nodes with a high common mode voltage can be challenging. The challenges can include isolating the high common mode voltage from as many components in the circuit as possible to minimize circuit size and to maximize performance; minimizing the load imposed by the sensing circuit on the nodes to be sensed, particularly when the nodes have a high source impedance, such as when they are at the output of an RC noise filtering circuit; and minimizing the noise generated by the voltage sensing circuit to maximize accuracy. Achieving all of these goals simultaneously can be particularly challenging.